The long-term objective of the current research is to determine whether olfaction serves as a channel of human communication, to explore the nature of and individual differences in such communication, and to compare it with human detection and processing of conventional odors. The application tests the hypotheses that biological odors salient for individuals' safety and reproductive success (e.g., fear, sexual arousal) are more easily detected and recognized, and that experiential factors (emotional intimacy with the donor) facilitate such detection. The specific aims are to examine: 1) olfactory discrimination and verbal identification of emotions via chemosignals, and 2) individual differences (experience, gender specificity) in sensitivity to the chemosignals. Chemosignals consisting of a mixture of aprocrine and eccrine secretions collected from men and women when they are under different emotional states will be used. A series of interrelated tasks including evaluation, ranking, and identification will be administered in a double-blind fashion. Established olfactory and emotional measures will be taken. This proposed study addresses a relatively unstudied area and may serve as a new model of olfactory research. It opens up the possibility that olfactory deficit, often conceptualized as a sensory process, may have a more direct social basis and link to mental health (affective disorder) than is currently appreciated.